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| REQUESTING OBSERVING TIME AND DELIVERED DATA |
How Do I Submit an Observing Request? |
As a user of the Tenagra II telescope you are assigned a place on our FTP server. Each user uploads an ASCII file in a precisely defined format so that the scheduler can read all requests and place them in optimal order. You just need to specify the night(s) in which you wish to observe each target; the scheduler will choose suitable observation times for each of your targets
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| Please follow these guidelines when
uploading observation requests to our FTP server: |
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Files containing observation requests must contain only observation requests in the format to be described below. Each observation request consists of a single line. Do not use tabs to format the columns. The name of files that contain observation requests cannot have blank characters.
- Files containing observation requests must have extension
.txt
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Files containing observation requests must be uploaded to the
root directory of your FTP area, not to any subdirectory.
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Observation requests meant to be carried out on the next night at
Tenagra must be uploaded to our server before 22:00 UT. For example,
if you wish to observe some target on 2003 Sept. 20 UT, the deadline for
uploading your observation request is 2003 Sept. 19, 22:00 UT.
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After each uploaded file containing observing requests is processed by our software, a receipt will be sent to you by e-mail and also placed in subdirectory /receipts of your FTP area. You should check this receipt to see if your observing requests were accepted; if some requests were not accepted, the reasons for the rejections will be given. The receipt also lists the serial numbers assigned to each of your accepted requests. These are unique numbers which identify each of your observing requests in our internal bookkeeping system.
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If you decide to cancel some of your
observation requests, please contact
us as soon as possible, specifying the serial number(s) of the
request(s) you wish to cancel. The above 22:00 UT deadline also applies to
the cancellation of user requests. |
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| Types of Observing
Requests |
This section describes the four types of observation requests which we can
accept at this time. Click on the links below for a detailed description of the
format of each type of request. |
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Non-solar
system objects. This category includes every object that is not in the
solar system (therefore not moving with respect to the stars), from the
closest stars to the most distant galaxies.
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Solar
system objects without a published ephemeris. These objects
will usually be new, relatively slowly moving objects discovered by you or
some other observer, which haven't yet received an official designation from
the MPC, and therefore need to be confirmed on a second night. This option
makes the assumption that the target moves slowly enough that a Väisälä
ephemeris generated with the New Object
Ephemeris Generator is accurate enough to get the object in the telescope
field-of-view over a period of a few days after discovery. If you discover
a fast moving object or a comet, you should report it to the MPC immediately,
without waiting to get images on a second night.
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Mosaic
searches for new solar system objects. This mode allows you to do a
mosaic search for comets or minor planets. The Tenagra 0.81-m telescope allows
you to easily discover minor planets whose magnitude is fainter than the
limiting magnitude reached by the surveys LINEAR, NEAT, and LONEOS. You can
confirm your (slowly moving) discoveries on a second night using observation
requests of type (3). If you discover a fast moving object or a comet, you
should report it to the MPC immediately, without waiting to get images on a
second night.
- Spectra of non-solar system objects. It is now possible to request spectra of stars, galaxies, and other objects outside the solar system.
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| Delivered Data |
You will be notified by e-mail when some of your observing requests are
carried out. These notifications will also be placed in subdirectory /notifications of your FTP area.
Your images will be placed in your FTP area as they are taken, in a separate
directory for each night and telescope. For example, your images taken with the
32-inch telescope on 2003 Sept. 25 UT will be stored in directory /030925_32in. The directory corresponding to a given night will contain
the following subdirectories:
/images
/dark
/bias
/EveningFlat
/MorningFlat
Subdirectory /images contains your raw science images, which
will appear in the subdirectory as soon as they are taken by the telescope. If
you wish to download your images in near real time, you may use a FTP client
(such as the Windows program Bullet
Proof FTP) which can be configured to continuously monitor the subdirectory /images and automatically download new images as they appear. In this
way, you can usually have all your night's data on your computer soon after the
images have been taken.
Your science images will be named AAAnnnnn.fit, where AAA is
your 3-character user ID and nnnnn is a serial number. These serial
numbers are not significant from the user's point of view. All the information
you need is in the FITS headers of the files. We will soon be adding a file to
each night's directory which will make it easy for you to correlate these file
names with the serial numbers of your observation requests.
You may choose between three options for compression
of your science images: zip, FITS compression, and no compression.
Compressed images will lead to a reduction of roughly 50% in download time.
Zipped images may be unzipped with standard programs such as pkZip, WinZip, etc.
Opening FITS-compressed images requires the Windows program MaxIm DL. If you use
MaxIm DL for your image calibrations, FITS compression is probably the most
convenient compression method.
At the end of the night at Tenagra, a file named calibrate.zip is
created in subdirectory /images. This zip archive contains all the master calibration files (bias frames, dark frames, flat fields) which
are necessary for the calibration of your science images. The master bias and
dark frames are obtained by median combining three individual bias and dark
frames, respectively. The dark frames have an exposure time of 150 seconds; you
are supposed to scale the master dark frames when using them to calibrate
exposures whose exposure times are not equal to 150 seconds. The master flat
fields are obtained from 3-7 individual sky flats, which are bias- and
dark-subtracted and then median-combined.
We automatically take flat fields in the morning and evening. Flats
for U, R, V-band and unfiltered are taken in the evening twilight and stored in
subdirectory /EveningFlats. Flats for B, I-band and IR Blocked are taken
in the morning twilight, following the run, and stored in subdirectory /MorningFlats. If your observations do not include images taken in the B,
I, or IR blocked filters, all your flat fields will already be available at the
end of astronomical evening twilight at Tenagra.
Bias and dark frames are always taken in the evening before
observations, and stored in directories /Bias and /Dark,
respectively.
If you do not wish to wait until the calibrate.zip file appears in
subdirectory /images, you may retrieve your calibration files from
subdirectories /Dark, /Bias, /EveningFlat, and /MorningFlat. We store both the individual calibration files taken with
the telescope and master calibration files which are produced by median
combining the individual calibration files. You will probably wish to use these
master files for your calibrations; the individual calibration files are
provided in case you wish to prepare your own master calibration files by
combining the individual calibration files.
Our naming convention for master flat fields is MasterFlat_binN_BAND_OPT.fit.
This looks a bit complicated but it isn't. All master flat frames have the
prefix MasterFlat. Following this is the binning of your image. This is bin1 or bin2 for unbinned or 2X2 binning. BAND is the
filter used: clear (unfiltered), U, B, V, R, I, IRBlock. OPT is an
optional part of the name that will contain Center or not be present. Center means that the central 7.4 x 7.4 arcminute field of the CCD
detector has been used. Some examples: |
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| MasterFlat_bin2_U.fit |
Master U-band
flat field binned 2X2 over the full 14.8 x 14.8 arcminute field of the CCD
detector (512 x 512 pixels). |
| MasterFlat_bin1_I_Center.fit |
Master I-band
unbinned flat field over the central 7.4 x 7.4 arcminute field of the CCD
detector (512 x 512 pixels). |
| MasterFlat_bin1_V.fit |
Master V-band
unbinned flat field over the full 14.8 x 14.8 arcminute field of the CCD
detector (1024 x 1024 pixels). |
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The names of dark and bias frames are quite similar except there is no BAND: MasterNAME_binN_OPT.fit, where NAME is either Dark or Bias. Some examples: |
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| MasterDark_bin2.fit |
Master dark
frame binned 2X2 over the full 14.8 x 14.8 arcminute field of the CCD
detector (512 x 512 pixels). |
| MasterDark_bin1_Center.fit |
Master unbinned
dark frame over the central 7.4 x 7.4 arcminute field of the CCD detector
(512 x 512 pixels). |
| MasterDark_bin1.fit |
Master unbinned
dark frame over the full 14.8 x 14.8 arcminute field of the CCD detector
(1024 x 1024 pixels). |
| MasterBias_bin1.fit |
Master unbinned
bias frame over the full 14.8 x 14.8 arcminute field of the CCD detector
(1024 x 1024 pixels). |
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The names of individual calibration files follow these conventions:
Flat_binN_BAND_nnnn_OPT.fit
Dark_binN_nnnn_OPT.fit
Bias_binN_nnnn_OPT.fit
where binN, BAND, and OPT are as explained above and nnnn is a serial number.
On rare occasions, bad weather or other problems prevent us from obtaining a
full set of calibration files. If this happens on a night when we have obtained
science images for you, you will notice that the calibrate.zip file
either will not be created (if none of your calibration files has been obtained)
or will not contain all the calibration files you need. In these cases, you
should search the directories which store the images from the past few nights,
where you will normally find the calibration files you need. Unless there has
been a change in optical or camera configuration, calibration images from a
previous night will be virtually identical to those taken on the current night.
If on a given night spectra are taken for you using the Tenagra spectrograph, additional data files and spectrograph calibration files are placed in your FTP area. Click here for details.
The directory corresponding to any given night is kept on the FTP server for
10 days, and is then moved to another computer for back-up storage. If you need
to download data which is more than 10 days old, please contact
us, so we can temporarily restore it to the FTP Server.
If some of your images are seriously affected by clouds, please send
us an e-mail mentioning the UT date when the images were taken and the file
names of the affected images, so we may provide a refund. |
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If you have questions about the the
observation request format or about the above processes please e-mail them
to mbs@tenagraobservatories. |
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| If
you wish to set up an account on the Tenagra II telescope click here. |
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